Lighting fixture backplate



FIG. 1 is a side elevational view of the lighting fixture backplate in accordance with the design, illustrated in an environment of a lamp;

FIG. 2 is a rear side elevational view of the lighting fixture backplate in accordance with the design;

FIG. 3 is a right side elevational view of the lighting fixture backplate in accordance with the design, the left side being a mirror image thereof;

FIG. 4 is a front side elevational view of the lighting fixture backplate in accordance with my design; and,

FIG. 5 is a bottom plan view of the lighting fixture backplate in accordance with the design, the top side being a mirror image thereof.

The broken lines show the environment in which the article is used and are not considered part of the design claimed. 

The ornamental design for a lighting fixture backplate, as shown and described. 